Various diagnostic assays for in vitro determination of ligands in body fluid are known, including specifically: radioimmunoassay (RIA), competitive protein-binding radioassay (CPB), enzyme immunoassay (EIA), enzyme multiplied immunological technique (EMIT), enzyme linked immunosorbent assay (ELISA), fluorescent immunoassay (FIA), and hemagglutination inhibition (HAI) assay. The assays are based on the principle of optimizing the mutual affinity between the ligand and a specific antibody or other binding entity for that ligand. For a comprehensive review of methods and methodology, see Weetal's Immobilized Enzymes, Antigens, Antibodies, and Peptides, Chapters 4 and 9, Marcel DEKKER, Inc., New York, 1975, incorporated herewith by reference.
In one prior art procedure, described in U.S. Pat. No. 3,464,798, a surface active plastic stick inserted in a conventional test tube is used for binding an analyte for clinical assay purposes. A disadvantage of this procedure is that such a plastic stick must be specially fabricated, is costly to produce, and is inconvenient to work with.
In another prior art procedure, described in U.S. Pat. No. 3,646,346, the determination of proteins in aqueous samples is done by an RIA procedure in which for binding purposes the interior surface of plastic tubes is first coated with specific antibody and the resulting coated tubes are used for containing the samples and binding the labeled and unlabeled antibody-specific protein in the samples to provide an end point distribution that is readable as a quantitative showing of specific protein content of each sample. A difficulty with this procedure is that the coated tubes have to be specially prepared commercially or in house, and, must thereafter be maintained under refrigeration prior to use.
It is therefore an object of the present invention to provide polymer container means and an assay method employing the same which avoids the disadvantages of the prior art practices.
It is a further object of the invention to provide novel container means and an assay method employing the same which avoid the use of coated assay tubes and disadvantages thereof.
It is a still further object to provide novel container means for assay purposes that are cost-effective and readily adaptable to a wide variety of applications in analytical and clinical chemistry.
These and other objects, features and advantages of the present invention will become apparent from the following description of the invention and preferred embodiments thereof.